1. Field
Aspects of some example embodiments of the inventive concept relate to display devices. More particularly, aspects of some example embodiments of the inventive concept relate to DC-DC converters and display devices having the DC-DC converter.
2. Discussion of the Related Art
In general, a display device includes a display panel having a plurality of pixels arranged in a matrix form. Each of the pixels operates in response to a driving voltage. For example, each of the plurality of pixels included in an organic light emitting display may have an organic light emitting diode (OLED). The OLED generates light by coupling holes, which are provided from an anode to which a first power voltage (ELVDD) is applied, and electrons, which are provided from a cathode to which a second power voltage (ELVSS) is applied, in an organic material layer formed between the anode and the cathode.
The display device includes a DC-DC converter. The DC-DC converter changes an input power voltage to one or more power voltages used for driving the pixels. For example, a DC-DC converter may supply a high power voltage (the first power voltage) and a low power voltage (the second power voltage) to the pixels through power source lines. The range of drive current flowing through a display panel may increase as the size of the display panel increases. Therefore, conversion efficiency of the DC-DC converter with respect to the whole range of the drive current may decrease when the DC-DC converter is designed for large drive current. Additionally, conduction loss may increase as a result of relatively large internal resistance of the DC-DC converter. Conduction loss decreases conversion efficiency of the DC-DC converter and increases heat generated by the DC-DC converter.
The above information disclosed in this Background section is only for enhancement of understanding of the background of the present invention, and therefore, it may contain information that does not form prior art.